1. Field of the Invention
This invention is directed toward a support structure for stator vane segments used in a gas turbine engine. The invention is also directed toward an improved stator assembly in a gas turbine engine, which assembly incorporates the support structure. The invention is more particularly directed toward an improved stator assembly in a gas turbine engine that is fixed at its outer radial end and which assembly incorporates the support structure.
2. Description of the Prior Art
Second stator assemblies in gas turbine engines usually have the inner radial end of the assembly floating on a seal arrangement on the rotating shaft of the turbine. The outer radial end of the assembly must be fixed to the outer engine casing. This is usually done by a ring-like support structure. However, in fixing the outer end of the second stator assembly to the outer engine casing, thermal expansion of the stator vane segments can cause distortion of the support structure which in turn can cause distortion in the outer engine casing. Distortion of the outer engine casing can change blade tip clearances for the blades in adjacent rotor assemblies in the engine which can reduce the efficiency of the engine.
The distortion could be reduced by adequate cooling of the stator vane segments. However, it is difficult to efficiently cool the vane segments when they are fixedly mounted at their outer ends.